The present invention relates to a method for determining the quality achieved by different mobile devices in a mobile radio network, for example in a digital mobile radio network.
The quality of communication in a mobile radio network depends on the quality of its infrastructure, including the base stations and other fixed components of the network, as well as on the quality of the mobile devices used, for instance mobile telephones. Since mobile devices are consumer goods offered by various manufacturers in different price categories, they may be of very different quality. Moreover, the quality of communication depends on the installation of these mobile devices. For example, if a mobile telephone is used in a car with tinted windowpanes, the quality may be improved greatly if an exterior antenna is used.
In general, a network operator attempts to ensure a minimum level of quality for all his subscribers. Therefore, the requirements on the infrastructure must be adapted to those mobile devices used that have the worst quality. This approach does not provide any advantages for mobile devices with a better quality, and is thus a waste of resources. Therefore, the network operator has a strong economic interest in subscribers equipped with bad quality mobile devices exchanging their devices for better ones or in having inefficient installations improved.
The invention follows from this finding and aims at a method for identifying mobile radio users equipped with bad quality mobile devices, in order to arrange for them to exchange their devices or to improve their installations.
According to the invention, a server in the mobile radio network calculates for each mobile device at least one quality indicator from at least a plurality of connections with this mobile device. The user of a mobile device not fulfilling one or more of the quality criteria set will subsequently be informed, for example by means of an indication in his telecommunication bill or by means of an alphanumeric message in his mobile device.
In this way, the user is asked to replace his mobile device or to have it repaired, or to improve the installation, so that it will become easier for the network operator to ensure a minimum level of quality for every user.
The patent document U.S. Pat. No. 5,490,204 describes a method for testing the quality of the infrastructure in a mobile radio network. For that purpose, a test mobile device is used, which carries out different test calls at different points of a mobile radio network, in order to check the quality of various components in the network, for instance different base stations. The test device comprises a laptop computer controlled by an appropriate program and connected to a mobile telephone. An operator with this test mobile device drives through the area covered by the network to measure the quality of connections at different locations in the network. This method does not make it possible to check the quality of terminal devices.
The patent document WO96/07288 describes a system in which the quality of a mobile device is tested during log in. The quality control is based on information from the mobile device, for instance, a signal sent out by the mobile device, which signal contains a code for the type of mobile device. In a variant, the quality is determined by means of a data base of the network operator where the types of all the devices having a subscription to the network are stored. The transmitting power of the base stations as well as the tariffs used are adapted depending on the information provided by the mobile device or by the data base.
In the above method, the quality of the devices is determined once and for all, either in the mobile device or in the data base. Thus, this method does not make it possible to inform the user when the quality of his device is deteriorating, for instance, because of a technical problem or a bad installation.